nuttx/Documentation/platforms/arm/lpc2378/boards/olimex-lpc2378
..
index.rst
README.txt

There's not much here:

EXT1 - P3 0:7 are used for LEDs.

UEXT pin 3/4 -TXD2/RXD2- is UART2.

The board I have has the revision '-' of LPC2378 even though I got the board
more than 2 years after the chip revision was released :-( .
I can't get NuttX to work if I fully enabled the MAM.

I used FTDI ft232 usb-serial with nsh piping as seen on the screenshot.